Travis Pohlman checks for hot spots in the trees along Dull Knife Drive in the Highlands community area north of Hutchinson, Kan., on Monday, March 6, 2017. Grass fires fanned by gusting winds scorched swaths of Kansas grassland Monday, forcing the evacuations of several towns and the closure of some roads, including a couple of short stretches of Interstate 70. (Lindsey Bauman/The Hutchinson News via AP)

The Kansas Division of Emergency Management said late Tuesday that the heaviest damage is in Clark County, where 548 square miles have burned. That fire started in Oklahoma before moving into the Kansas ranching community.

Another 235 square miles have burned in neighboring Comanche County, Kansas.

The state says six other counties are battling blazes. Among them, estimates of the burned land range from a single square mile to about 90.

Kansas National Guard Black Hawk helicopters have been assisting with the firefight. They dropped about 138,000 gallons on fires near Hutchinson in Reno County, where 10,000 to 12,000 people voluntarily evacuated their homes.